The Mid-Atlantic Ridge (Part 1): The Powerhouse of Earth

This blog post will focus on some of the features of a little known geological treasure of Earth; the Mid-Atlantic Ridge. This ridge is a divergent tectonic plate boundary between two pairs of tectonic plates (North and South American, and the Eurasian and African plates), which pull apart form each other. In the case of the Mid-Atlantic Ridge, this occurs at a speed of 2.5cm a year. Magma from inside the earth's crust rises up out of this fault, and over millions of years mountains are created. The Mid-Atlantic Ridge runs from off the north east cost of Greenland to the far south of the Atlantic ocean. At 10000 miles (16000 kilometers) long, the Mid-Atlantic Ridge is the longest mountain range on Earth.

The Mid-Atlantic Ridge can be seen as the light-blue spine running down the centre of the Atlantic

https://commons.wikimedia.org/wiki/File:Atlantic_bathymetry.jpg

The Mid-Atlantic Ridge is a very volcanic environment. The sea-floor of this area is littered with hydrothermal vents which raise the sea temperature from near 0 degrees Celsius to up to 450 degrees. These sort of temperatures produce an environment so different from the rest of the underwater world that they harbour their own ecosystems. At these depths, no organism can rely on light in the same way that plant life on land can. Heat resistant bacteria instead sustain themselves with nutrients derived from vent-produced chemicals, by use of a process called chemosynthesis. Some of the most ancient organisms ever discovered have been thermophiles, and the Deep Sea Vent Hypothesis suggests that life itself may have its origins in this peculiar environment. 

 Chemosynthesising bacteria on the floor of the Mid-Atlantic Ridge provide the foundation of a diverse ecosystem.

http://oceana.org/marine-life/marine-science-and-ecosystems/deep-hydrothermal-vent

These 'thermophilic' bacteria can be of use in industrial processes, where changes in temperature would render other biological agents useless. Perhaps the most famous example is the use of Thermus aquaticus (Taq) bacteria, from geothermal vents in Yellowstone National Park. The DNA polymerase from Taq is used at high temperatures in the Polymerase Chain Reaction (PCR) to replicate DNA. This process has a wide array of applications from genetic testing in healthcare to isolating and identifying genetic material in criminal forensics. 

On the topic of marine ecosystems that flourish along the Mid-Atlantic Ridge, I'll finish with this photo, taken in the geothermal pools in Iceland (also along the Mid-Atlantic Ridge).

A thermophilic organism

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Counties of England: The Myth of Middlesex

I go to university in North London, where the identity of the County of Middlesex is quite deeply ingrained into the fabric of the area. Many people who live nearby will associate themselves with the County by using it as part of a postal address, and a nearby University is named after it. If you hang around the student union bar on Gower Street long enough on a Wednesday sports-night, you may even hear the echoes of a tribute to the County:

Middle Middle Middle...
SEX! SEX! SEX!

With this in mind I realise I'm being controversial when I entitle my blog "The Myth of Middlesex". This blog post will briefly outline the evolution of Middlesex and English Counties as an administrative unit; including some of the out-of-date terminology that is still in common usage today.

Middlesex was a historical county of England, which encompassed much of North and West London including, amongst other areas, Barnet, Enfield, Uxbridge, Harrow and Staines-Upon Thames. It was considered by many to be the 'County of London', as it included the East and West End of the city and as a County had no formal County town (the 'capital' of a County, if you will). The map below shows Middlesex in relation to the surrounding Counties in the South East of England:

Adapted from: https://commons.wikimedia.org/wiki/File:English_counties_1851_with_ridings.svg

However, the map above was adapted from a snap-shot of a map of Counties as they stood in 1851. They have undergone fairly substantial change since then. The first major alteration to the County of Middlesex was the creation of the County of London in 1889, which siphoned of some of inner-London into a purpose made metropolitan County. With the implementation of better transport links to the region surrounding London, Middlesex became more and more integrated into the capital. In 1963, as part of the London Government Act, Middlesex was fully absorbed into the newly created metropolitan county of Greater London (below), with small amounts going to surrounding counties. As an administrative entity, Middlesex did once exist, but has not now for over 54 years. 

Adapted from: https://commons.wikimedia.org/wiki/File:English_ceremonial_counties_1998.svg

The definition of a 'County' is still somewhat fluid. Nowadays, the ceremonial Counties of England are co-terminate with Lieutenancy Areas, which have a designated Lord Lieutenant. This is the Monarch's representative in each County, and is a largely ceremonial position. The reason these are called 'ceremonial' is that in practical terms, a place may be administered as part of a County Council (i.e. Devon County Council, Somerset County Council, etc.) or a unitary authority, which is common for large towns and cities. I won't bore you with tons of maps, as the borders of English Counties change frequently. However some important historical Counties, which no longer exist in either a ceremonial or administrative form include:

• Huntingdonshire, which is now a part of Cambridgeshire
• Sussex, which is now split into East and West Sussex
• Yorkshire, which is now split into four separate counties
• Westmorland, which is now a part of Cumbria
• Avon, which is split between Somerset, Gloucestershire and the metropolitan County of Bristol

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Sri Lanka: When An Island Becomes An Island

I apologise for the delay in writing this blog post. Islands are my favourite geographical feature, as you can probably tell from the content of my blog so far. However, I want my blog to have a broader approach to both physical and human geography. After my last post about the Diomede islands, I promised to myself that my next post would focus on something other than islands.

So by the inclusion of Sri Lanka in the title of this post, you probably now think a promise of mine is not very valuable at all. If you keep reading, I may be able to convince you otherwise, however if I can't I hope you enjoy the post regardless.

Glance across a map of the world, or of South Asia specifically, and you will see the unmistakeable 'tear-drop' shaped outline of Sri Lanka, sitting off the south-east coast of India. Sri Lanka punches well above its weight in terms of biodiversity, and is said to be one of a few countries where you can see both elephants and blue whales- the largest mammals of the land and sea, respectively. The flag of Sri Lanka is a favourite of flag enthusiasts, as it has been designed to represent the huge ethnic, cultural, and religious diversity of the island.

https://commons.wikimedia.org/wiki/File:Flag_of_Sri_Lanka.svg

However, Sri Lanka has not always been an island. Submerged in the water between India and Sri-Lanka is a collection of limestone shoals, known as Rama's Bridge (also, Adam's Bridge). This geographical feature has significance in Hindu Literature; believed to have been built by Rama's army to connect Sri Lanka to the continent. There is no consensus amongst Geologists as to the origin of the feature, but they believe it may be the remnant of the tombolo created by Sri Lanka's separation from the continent.

https://www.google.co.uk/maps/@9.1922377,79.4665992,235630m/data=!3m1!1e3

While geological events such as continental drift may occur over millions of years, the sinking of Rama's Bridge occured far more recently. In fact, there is evidence to suggest the bridge was patent until the 15th Century, when it was wiped out by a powerful cyclone. Sri Lanka, by a wisp, was connected to the Indian Subcontinent. 

At the very tip Pamban Island, on the Indian side of the Palk strait, lies a ghost town known as Danushkodi, which was destroyed in a 1964 cyclone. I've read a source which claims that here lies a 45 yard long border on a sand dune between India and Sri Lanka which persists today, making it one of the world's shortest land borders. Sadly, I cannot find any official recognition of this border, so I'll leave it up to you to decide whether you believe it or not.

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The Diomede Islands: The Town Where You Can Gaze Into Tomorrow

Situated in the Bering strait, the body of water which separates Russia from the USA, are the two Diomede Islands. The larger of the islands, aptly named Big Diomede, is owned by Russia. Just 3.8 kilometers East is the smaller island, Little Diomede, part of the US State of Alaska. These islands are thought to be the last remnants of a land bridge, which connected the continent of Asia to North America during the last Ice Age.

https://www.maritimeprofessional.com/blogs/post/diomede-islands-13618

The International Date Line (IDL) is an arbitrary line which runs from North to South around the 180th Meridian, which demarcates the end of one day and the beginning of the next. As time zones are defined locally by individual nations, the IDL swerves around territorial boundaries. Rather interestingly, therefore, the IDL passes between the two Diomede Islands. Meaning at a given time, Little Diomede is a calendar day behind Big Diomede. By standing on one of the islands, you can effectively look either into the future or into the past*. 

The islands are not uninhabited either. The island of Little Diomede is home to a small Inupiat village called Inalik (below), which has a population of 115. In Winter, the waters between the islands freeze, allowing people to cross between the islands- effectively becoming a land border between the USA and Russia. During the Cold War, such crossings were no longer permitted, and the border between the Diomede islands was known as the 'Ice Curtain'. Although now more relaxed, border restrictions between the two countries prevent the native population from reuniting with their relatives in Russia.

https://commons.wikimedia.org/wiki/File:Little_Diomede_Island_village.jpeg

*Due to locally defined time zones, the two islands are 21 hours apart, rather than a whole day. So if you were hoping to 'look into the future' on Little Diomede, you should do it after 03:00.

Islands And Lakes: Well Isle Be Damned...

The largest island in the world, at 2,166,086 square kilometers (8.9 times larger than the UK), is Greenland. Below is a size comparison of Greenland with the contiguous United States. Despite this, Greenland has a population of just over 56,000, making it one of the most sparsely populated areas on Earth. The largest lake is the Caspian Sea, at 371,000 square kilometers, in Central Asia. But of course, you may have learnt this already back in Geography class- and that isn't the point of this blog!

http://www.mylifeelsewhere.com/country-size-comparison/united-states/greenland

Islands within lakes can themselves be an important geographical feature. Grand Isle County, Vermont, is an entire county in the US comprising of lake islands within Lake Champlain. So what is the largest lake island in the world? Manatoulin island (below left), a Canadian island situated in lake Huron, is the largest. At 2766 square kilometers, it is larger than the nation of Luxembourg. The second largest lake island is René-Levasseur island in the Canadian province of Quebec. This circular island (below right), is intriguing for a number of reasons. Firstly, the island and its annular lake, the Manicouagan reservoir, are situated in the crater of one of the largest known prehistoric meteor strikes. Secondly, it is actually an artificial island, created from flooding two existing lakes in 1970. At 2020 square kilometers, it is the largest artificial island in the world. Finally, René-Levasseur is a rare example of an island which is larger than the lake in which it is situated. 

https://commons.wikimedia.org/wiki/File:Manitoulin_Island.jpg

https://commons.wikimedia.org/wiki/File:Manicouagan-EO.JPG

We can go further, and talk about the largest lakes on islands, and lake islands within them, and lakes on those lake islands. However, I think this would be dull and repetitive. Instead, I've summarised the largest of these various configurations of lakes and islands in the diagram below:

If you really want a headache, think about the island in a lake, on an island in a lake, on an island; a 'third order island'. The largest of these was discovered in 2012 by famous game show contestant and author, Ken Jennings, who spotted it after spending hours scanning Google Earth. The 4 kilometer squared island is located on Victoria Island, Canada and is as yet unnamed and uninhabited. It is highly probable that humans have never even set foot on this unusual piece of land.

https://earthobservatory.nasa.gov/IOTD/view.php?id=85342

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International Waters: What Makes The 'Peanut Hole' So Salty?

A country with a coastline can exert legal influence on some of the waters that surround it. Internationally agreed maritime laws allow countries to have complete jurisdiction over waters within 12 nautical miles of their coast (territorial waters), and a few more limited rights over waters within 200 nautical miles; the Exclusive Economic Zone (EEZ). Boats of any country can come and go here, but countries can set laws that prevent economic hindrance to their territory, such as the right for international vessels to fish. Beyond this, international waters persist, which are not under the jurisdiction of any country. International waters, or the high seas, are denoted in dark blue on the map below:

https://commons.wikimedia.org/wiki/File:International_waters.svg

As you can imagine, disputes over territorial waters and EEZ can get very complicated, depending on who has jurisdiction over a piece of coast, or even whether an island truly counts as an island. The complexity of a country's maritime jurisdiction only increases if a country is very large, or has many islands.

Russia, being the largest country in the world, and having one of the largest coastlines, is no exception to this. An example of where rules over international waters can get quite sticky is in the Sea of Okhotsk. The sea is surrounded mainly by Russia, and so Russia's EEZ extends 200 nautical miles inwards. This covers almost the entire body of water, except a strip of water in the centre, which measures 35 x 300 miles. This is known colloquially as the 'Peanut Hole'. It is shown below, on a close-up of the Sea of Okhotsk:

https://commons.wikimedia.org/wiki/File:Peanut_Hole.jpg

As previously mentioned, boats can enter the EEZ freely, however a country can set down laws such as prohibiting fishing by foreign vessels. Prior to 2014, Russia had no such jurisdiction over the 'Peanut Hole'. the result was some countries- notably Japan, China, South Korea and Poland- entering the region and fishing. This caused quite a headache for Russia, who feared their straddling fish stock, such as Pollock, could be affected. 

Russia ended up petitioning the UN who, in 2014 agreed, and determined the 'Peanut Hole' to be part of a continental shelf that belonged to Russia, and gave them rights to set laws that govern international fishing rights. 

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